This invention relates to radar reflecting flotation devices, and more particularly to life vests and life rafts with reflecting properties to permit radar indication of its location on the surface of large bodies of water from long distances to aid in search and rescue efforts.
Search and rescue missions to locate personnel in large bodies of water are often difficult and the methods used vary in effectiveness. Currently, the best way to search for personnel is to use an Emergency Position Indicating Radiobeacon (EPIRB). However, these units tend to be expensive and only operate for a limited time and are often not available to the person in need of rescue. Visual identification is probably the most common form of search and rescue. Some life vests and life rafts have flashing light beacons to aid in a visual search at night. However, any visual search effort needs good weather and has a very limited range.
Previous U.S. patents have addressed the use of some form of radar cross section enhancer to permit radar to be used to locate objects at sea that by themselves are usually poor radar reflectors and are virtually indistinguishable from the radar return of the surrounding sea. Usually, these have taken the form of either an inflatable or fixed radar reflector that may be added to a life raft or attached to a person in the water. These radar reflectors incorporate corner reflector arrays that provide radar cross-section (RCS) many times greater than the same sized object without corner reflectors. These systems work well when deployed. However, persons in need of rescue often do not have access to these add on devices. Many times the only item a person has is the personal flotation device they are wearing.